Flask



FIG. 1 is a front perspective view of a flask, showing my new design;

FIG. 2 is a top perspective view thereof;

FIG. 3 is a front view thereof, the rear view being a mirror image thereof;

FIG. 4 is a left side view thereof, the right side view being a mirror image;

FIG. 5 is a top plan view thereof; and,

FIG. 6 is a bottom view of the flask. 

I claim the ornamental design for a flask, as shown and described. 